f] 



The Nautilus. 



Vol. VI. JANUARY, 1893. No. 9 



CATALOGUE OF THE GENUS PAKTULA. 



BY W. D. HARTMAN, M. D. 



(Concluded from November number.) 



The genus Partula propo.sed by Baron Ferussac in 1819, is 

 restricted to certain small land shells inhabiting the Pacific Islands. 

 The species are found throughout all the groups of these islands, 

 and as far west as New Guinea, which seems their limit. North of 

 the equator they are found at the Caroline, Pelew and Ladrone 

 Islands, and recently the Solomon and New Hebrides Islands have 

 afforded several new species. They have not been found at the 

 Sandwich Islands, New Zealand or Australia. In the Viti group, 

 Mr. Andrew Garrett has discovered that some species are restricted to 

 a single valley, each of which has its specific center, and the range of 

 many species is quite circumscribed. In the Marquesas group some 

 species are found on top of the highest mountains, like many other 

 land shells. The species are either arboreal or terrestrial ; hybrids 

 are often found, and they occur between arboreal and terrestrial 

 species. Some hybrids appear to possess a certain degree of fertility, 

 and Mr. Garrett informs us that ten species in the Viti group have 

 produced local varieties. The shells of some species are stout and 

 solid, while others are thin and attenuate. Many species have a 

 tooth-like projection from the inner margin of the peristome giving 

 the aperture an auricular appearance; nearly one half of the 

 species possess this button-like tooth on the parietal wall. In- 

 dividuals of some species are entirely sinistral while others are 



